Actuallly there is an application that does this, or claims to do this. Spy Phone Location Tracking and Remote Listening Software for Blackberry Mobile Phones - FlexiSPY PRO Blackberry Spyphone
Someone would have to have access to your phone to install it. It's not cheap, so someone would really want to track you to spend 150 Euro or what ever the dollar equivalent is now.
If someone really did install this and is tracking you, it is very likely a violation of wiretapping laws. Some info about it here: Wiretapping and Eavesdropping on Telephone Conversations
Should you want to file charges against the person who installed it and is tracking you, you would have to have evidence to prove it. I don't know if there are people around who can do forensic analysis of a BlackBerry. If you want the spying application off the device, wiping it as others suggested will do that.
If it's an abuse situation (not saying it is), it should be reported to the police after you can get to a safe place away from the abuser. If its an abuse situation, this information could apply. Internet and Computer Safety